1. Field of the Invention
The present invention relates to a novel high fixation ink composition for digital textile printing. More particularly, the ink composition comprises a reactive dye compound with two reactive groups.
2. Description of Related Art
Over the years, digital ink printing has received increasing attention. The current ink used for digital textile inkjet printing is formulated using a traditional dye comprising a single reactive group. However, there are disadvantages when such traditional dyes are used. For example, reactivity of dyes comprising a single reactive group to fabric is weak. Coloring by dyes comprising a single reactive group is uneven. Fixation rate of dyes comprising a single reactive group is poor. In general, the fixation rate of a printing ink formulated using a dye comprising a single reactive group is only 50% to 70%. With such a low fixation rate, 30% to 50% of unfixed dye is usually washed off. Subsequent treatment of colored wastewater is always required. However, treatment of colored wastewater is usually very complicated.
In addition, since the reactive groups of most reactive dyes are halogen group or nicotinic acid, these reactive dyes are prone to hydrolysis. As a result, the pH value of printing ink is usually low, causing the storage stability of printing ink to be poor. Therefore, the storage and expiration date of printing ink are usually affected.
Accordingly, there is a need to develop an ink composition with high pH stability, high fixation rate, and high coloring concentration for digital textile inkjet printing of fabrics.